Double-acting rectifier arrangement cooperating with at least one alternating current-excited electromagnet, particularly an electromagnetic relay



Nov. 7, 1950 o. TSCHUM] 2 ,529,118

DOUBLE-ACTING RECTIFIER ARRANGEMENT COOPERATING WITH AT LEAST ONE ALTERNATING CURRENT-EXCITED ELECTROMAGNET, PARTICULARLY AN ELECTROMAGNETIC RELAY Filed Dec. 50, 1947 6 Fig? v: e a 1 L7 I l H; a e a e I e, a

Fig.2

Fig.3

- M W! T\ I r w f )L r- F 0/1 TZZL m/ Patented Nov. 7, 1950 DOUBLE-ACTIN G RECTIFIER ARRANGE- MENT COOPERATING WITH AT LEAST ONE ALTERNATING CURRENT-EXCITED ELECTROMAGNET, PARTICULARLY AN ELECTROMAGNETIC RELAY Otto Tschumi, Soleure, Switzerland, assignor to Autophon Aktiengesellschaft, Soleure, Switzerland Application December 30, 1947, Serial No. 794,577 In Switzerland July 18, 1945 Section 1, Public Law 690, August 8, 1946 Patent expires J uly 18, 1965 Claims.

Double-acting rectifier arrangements with two or four cells in cooperation with electro-magnets are known. Such arrangements enable to use direct current magnets, particularly direct current relays to be used in alternating current circuits without such magnets having the tendency of buzzing.

Furthermore, direct current relays with retarded action are used for the same purpose, with a half-wave rectifier in parallel or in series. The disadvantage of the first mention d alternative is the considerable quantit of rectifiers, whereas the disadvantage of the second alternative is that the excitation o t ut is relatively small owing to the second half-wave being inactive, thus there exists a tendency to buzz. s

. In the double-acting rectifier arrangement according to the invention, cooperating with at least one alternating current-excited electromagnet. particularly an electro-magnetic relay such disadvanta es are avoided. In this ca e, the electro-ma net possesses two magnet callyopnosed windin s. The ampere-turns of the two windings are difierent. A half-wave rectifier is connected with respect to the winding possessing the higher number of am ere-turns in such a manner that one half-wave of the alternating current flows throu h this windin wh reas both half-wave flow through t e other winding.

Ex cut on l iorms accor ing to the invention ar illustrat d in the drawing.

Fi 1 shows n elec ro-ma n t w th two windin in coo eration with rectifier valve.

F g. s ows a cir uit with t o r la s and with a rectifier ell or prod cing impuls ons.

Fig. 3 shows in a diagram the imoulsions of the executional form according to Fig. 2 in function of the lternating current waves.

Fi 4 shows a further electro-magnet with two windin s in coo eration with a rect fi r valve.

The electro-ma net EM to be excited (Fi 1) possesses the two ma gnetically-opposed windings W1 and W11. which are so dimensioned that the number of ampere-turns of W11 is higher than that of W1. The rectifier G is in parallel with the winding W11. The working of the arrangement is the following:

For half-wa e I (see Fig. 3) the r ct fier shortcircuits the winding W11. Thus. only the winding W1 is being excited. For half-wave 2 the rectifier ofiers a high resistance. The current flows not only through the winding W1, but also through the winding W11. The excitations of both windings act in opposite directions. Owing to the fact that the excitation of winding W11 is higher than that of winding W1, the field of the electro-magnet EM possesses the same direction as during half-wave l, i. e. the magnetic flux of the system does not change its direction. The armature of the electro-magnet is not likely to buzz.

R1=resistance of winding W1 Rz=resistance of winding W11 R=R1+R2 n1=number of turns of winding W1 n2=number of turns of winding W11 U=applied alternating voltage AW=number of ampere-turns,

then, we may write:

U.n =act1ve number of ampere-turns during half-wave 1 U AW -(n n )act1ve number of ampere-turns during half wave 2 respectively It has been particularly advantageous to make AW1=AW2, when Buzz is equal n1.(R+R1) and it follows that If, for example, we make R=2R1, then we obtain In Fig. 2 is illustrated a further executional -form.

The two relays I and II possess each two different windings A and B which are connected in series and opposing each other. The relay I is provided with the working contact I1 and the relay II with the c'hange-over contact 111. The excitation of winding IA during working is sufficient to actuate contact I1. Similarly the ex- 3 citation of winding IIB is sufiicient to actuate contact III.

The working is the following:

The rectifier G forms a short circuit for halfwave l. Thus, during this half-wave current flows through the winding IA. This actuates the contact II. The following half-wave 2 goes through the windings IB, H13 and IA. The relay II is being excited and the change-over contact II: actuated. The relay I still retains its armature in attracted position because current still flows through the winding IB- During the next change of direction, that is during the half-wave 3, no current flows through the windings IB and HE because the rectifier does not exert a cutting action. The relay I is not excited, whereas the relay II is excited through winding IIA. At the end of half-wave 3, the armature of relay II is also released due to the cutting action of the rectifier. The circuit enables to obtain, by means of special contacts of relays I and II, not shown in the drawing, two series of impulsions a and p which in function of time, show for example the shape as represented in Fig. 3.

A further executional form of the arrangement according to the invention is shown in Fig. 4. W: and Wu again represent two magnetically: opposed excitation windings of the electro-magnet which are connected in parallel and s dimensioned that the number of ampere-turns of Wu is higher than that of WI. In series with the winding W1; is arranged a half-wave rectifier G, The Working of the arrangement is as follows:

The half-wave I passes through the rectifier; current flows through both windings. The magnetic flux in the iron circuit of electro-magnet EM is equal to the difference of the two field components. During half-wave 2 the rectifier G exerts a cutting action, thus current flows only through the winding I. The existing magnetic flux possesses the same direction as the field during half-waveI.

If we take again. AW1=AW2, then we may write in R1 and we have for 2R1=2R21 What I claim is:

1. In an electromagnetic circuit the combination of an alternating current-excited electromagnet comprising two magnetically-opposed windings having difierent ampere turns, a halfwave rectifier connected in series with one of the said windings and connected in parallel with the other of the said windings.

2. In an installation according to claim 1, the said windings being connected in series, and said rectifier being connected in parallel with the winding possessing the higher number of ampereturns.

3. In an installation according to claim 1, said windings being connected in parallel, and said rectifier being in series with the winding possessing the higher number of ampere-turns.

4. In an installation according to claim 1, the said windings being connected in series, and said rectifier being connected in parallel with the winding possessing the higher number of ampereturns, the same resultant number of ampereturns being effective during both half-waves.

5. In an installation according to claim 1, said windings being connected in parallel, and said rectifier being in series with the winding possessing the higher number of ampere-turns, the same resultant number of ampere-turns being effective during both half-waves.

. OTTO TSCHUMI.

REFERENCES CITED The following reierences are of record in the file of this patent: v

UNITED STATES PATENTS Abell June 1, 1943 

